The invention relates to a television camera comprising a picture pick-up device, a scanning signal generator for the line or field scanning respectively during the line-by line and field-by-field conversion by the pick-up device of optical picture information into a video signal occurring with line and field periods laid down in a television standard and a signal processing circuit for improving the picture quality on display by combining information of adjacent lines for forming the video signal.
A television camera comprising a signal processing circuit arranged for performing a vertical aperture correction is disclosed in U.S. Pat. No. 3,629,498. It is indicated that by using the interlaced line scanning prescribed in television standards, the combining of the signals of directly adjacent lines requires a delaying element having a delay time of one field period, whereas two delay elements having a delay time of one line period are sufficient if not the directly adjacent but the lines situated one line further on are utilized. The use of a delay element having a time delay of one field period has the drawback of motion unsharpness in the case of moving components in the scene to be televized which move during the field period. The use of delay elements having a time delay of a line period has the drawback of a gross accentuation of signal transitions on display; the information of places (lines) which are too remote from one another are utilized for signal combination.
Said Patent discloses a vertical aperture correction circuit in which a combination of a delay element having a time delay of one field period and two delay elements having a time delay of two line periods are used, eliminating the drawbacks of both.